It is well known in the art to utilize a CMM to measure objects in a space in terms of their X, Y, and Z coordinates commonly referring to length, width and height. Advancement in the art has led to lightweight portable CMM's well suited for general industrial applications. Such a CMM is disclosed in U.S. Pat. No. 5,402,582 which is commonly assigned to the assignee hereof and incorporated herein by reference. Three dimensional objects are described in terms of position and orientation; that is, not just where an object is but in what direction it points. The orientation of an object in space can be defined by the position of three points on the object. Orientation can also be described by the angles of alignment of the object in space. The X,Y, and Z coordinates can be most simply measured by three linear scales. In other words, if you lay a scale along the length, width and height of a space, you can measure the position of a point in the space.
Presently, coordinate measurement machines or CMM's measure objects in a space using three linear scales. Coordinate measuring machines of the prior art comprise a multijointed (preferably six joints) manually positional measuring arm for accurately and easily measuring a volume which typically comprises a sphere preferably ranging from six to eight feet in diameter (but which may also cover diameters more or less than this range). In addition to the measuring arm CMM's of the prior art employ a controller (or serial box) which acts as the electronic interface between the arm and a host computer which displays menu prompts and outputs to an operator. The mechanical measuring arm used in CMM's generally comprise a plurality of transfer housings (with each transfer housing comprising a joint and defining one degree of rotational freedom) and extension members attached to each other with adjacent transfer housings being disposed at right angles to define a movable arm preferably having five or six degrees of freedom. Each transfer housing includes measurement transducers. In addition, each transfer casing includes visual and audio endstop indicators to protect against mechanical overload due to mechanical stressing.
Measurement arms for CMM's include a probe handle assembly at the operator end. Probe handle assemblies of the prior art include hand grips that are held by an operator as either a pencil or pistol grip and sometimes possess two switches for the attachment of optional electronics and/or a threaded mount for receiving a variety of probes. Because the CMM is a manual measurement device, the user must be capable of moving the arm using the handgrip in the taking of measurements and then confirming to CMM whether the measurement is acceptable or not. Hand grips are presently rigidly mounted to the probe end handle assemblies and are typically arranged for use by a right handed operator. Although these hand grips function adequately for manipulating the arm they can increase the fatigue of operator and prove inconvenient during the taking and confirming of measurements.
A variety of probes may be threaded to a probe handle assembly such as a hard 1/4 inch diameter ball probe or a point probe is shown. The probes are typically threadably mounted to mount which in turn, is threadably mounted to a probe housing and may also include a plurality of flat surfaces for facilitating engagement and disengagement of the probes using a wrench. The use of different probes with prior art hand grips also may increase the level of fatigue and operator difficulties.
What is needed is an multi positionable ergonomically shaped hand grip capable of adjustment for a variety of operators.